1. Field of the Invention
This invention is a device containing a locking bar which cooperates with a locking arrangement. The device is to be used for doors, stores, containers and for protection for lorry building-ups.
2. Description of Related Art
A lot of different devices for locking doors and similar in connection with a locking bar are earlier known. These generally consist of a rotating or telescoping locking bar which can be locked in some way to a block house. The degree of security against burglary and destruction of these arrangements vary significantly. In Sweden such burglary protecting fittings and locking arrangements are classified by the Burglary Protection Association (SSF) and the Insurance Companies' Service AB (FSAB). Classification is divided in five steps where 5 is the highest grade of classification that can be reached. Extremely hard tests are to be performed to be able to reach class 5, and therefor such classification is very rare. Most constructions of high class achieve, because of this, classification grade 4 or lower. To be able to reach this class both fitting and locking device must resist stretching strengths of 7000 kilopound. This is to be compared with that of the strength which all latch locks have is of the measure 700 kilopound thus 1/10 of what is required for classification in class 4.
An example of earlier known locking arrangements involving a locking bar is described in Swedish patent 8301668-3. This device involves a locking bar which is removable in a loop on one of the doors and which is removable in the locking device on the other door. The loop in the first door is anchored on the plate with a bolt hole going through for fastening in the door. The bolts are thus reachable from the outside and can easily be sawn off. The locking device in the other door involves a house which is welded on a carrying plate which can be bolted in a similar way to the bottom layer. Moreover on the house a further protection is welded. This protection does not stretch itself around the whole house and it is welded on the upper side only. With the help of tools it is therefore easily broken off.
The locking bar in this known device has one side open and consequently it can therefore be exposed to blows or any pressure whatsoever. The latch bolt from the locking house can thus be blown off. Another inconvenience with this device is that if this locking device involving a key should break, the whole locking arrangement must be discarded. The lock house is namely by different weldings which are not exchangeable.
Further devices for locking doors are described in U.S. Pat. Nos. 4,106,315, 4,905,486 and 4,548,058. Characteristic of these patents is that in spite of good production they are simple to break on account of easy reachability with tools. They also have a complicated construction and are consequently expensive in production. By eventual damage on the locking mechanism the whole device has to be thrown away as exchangeable parts do not exist.